Dr Eric Guiry

Growing up in Canada, I developed a keen interest in the natural world and understanding how people interact with their environment. I studied anthropology, archaeology, and biology during my undergraduate, and became interested in how chemical analyses of ancient proteins can be used to explore the lives of past peoples and ecosystems. Using these techniques, my graduate work investigated the socioeconomic roles played by animals in historical North America. My current research programme seeks to further broaden the ability of these analyses to help reframe our understanding of long-term environmental changes and human-animal relationships spanning the Holocene and across the globe.

My research focuses on how isotopic analyses of archaeological animal and human remains can be used to better understand:
1. The social and economic roles that animals have played in past societies;
2. Past ecosystem dynamics in order to explore how humans have altered their environments.

1. 2021 Guiry, E., Kennedy, J.R., O'Connell, M.T. et al. Early evidence for historical overfishing in the Gulf of Mexico. Science Advances, 7: eabh2525.
2. 2021 Guiry, E., Szpak, P. Improved quality control criteria for stable carbon and nitrogen isotope measurements of ancient bone collagen. Journal of Archaeological Science, 132: 105416.
3. 2021 Guiry, E., Noël, S., Fowler, J. Archaeological herbivore δ13C and δ34S provides a marker for saltmarsh use and new insights into the process of 15N-enrichment in coastal plants. Journal of Archaeological Science, 125: 105295. 
4. 2021 Guiry, E., Orchard, T.J., Needs-Hoawarth, S., Szpak, P. Isotopic evidence for garden hunting and resource depression in the Late Woodland of northeastern North America. American Antiquity, 86(1): 90-110. 
5. 2020 Guiry, E., Szpak, P. Quality control for modern bone collagen stable carbon and nitrogen isotope measurements. Methods in Ecology and Evolution 11(9): 1049-1060.
6. 2020 Guiry, E., Buckley, M., Orchard, T., et al. Deforestation caused abrupt shift in Great Lakes ecosystem. Limnology and Oceanography, 65(8): 1921-1935.
7. 2020 Guiry, E., Royle, T., Matson, R.G. et al. Differentiating salmonid migratory ecotypes through stable isotope analysis of collagen: Archaeological and ecological applications. PLoS 1, 15(4): e0232180.
8. 2020 Guiry, E., Orchard, T.J., Royle, T, et al. Dietary plasticity and the extinction of the passenger pigeon (Ectopistes migratorius). Quaternary Science Reviews, 233: 106225.
9. 2020 Guiry, E., Hunt, B.P.V. Integrating fish scale and bone isotopic compositions for ‘deep time’ retrospective studies. Marine Environmental Research, 160: 104982. 
10. 2019 GUIRY, E. Complexities of stable isotope biogeochemistry in ancient freshwater ecosystems: implications for the study of past subsistence and environmental change. Frontiers in Ecology and Evolution, 7: 313.
11. 2018 GUIRY, E., Buckley, M. Urban rats have less variable, higher protein diets. Proceedings of the Royal Society B, 285: 20181441. DOI: 10.1098/rspb.2018.1441
12. 2018 GUIRY, E., Beglane, F., Szpak, P., et al. Anthropogenic changes to the Holocene nitrogen cycle in Ireland. Science Advances, 4: eaas9383. 
13. 2018 GUIRY, E., Jones, B.M., deFrance, S., et al. Animal husbandry and colonial adaptive behaviour: isotopic insights from the La Belle shipwreck fauna. Historical Archaeology, 52: 684-699.
14. 2017 GUIRY, E., Szpak, P., Richards, M.P. Isotopic analyses reveal geographical and socioeconomic patterns in historical domestic animal trade between wheat and maize agricultural regions in eastern North America. American Antiquity, 82: 341-352. 
15. 2016 GUIRY, E., Needs-Howarth, S., Friedland, K.F. et al. Lake Ontario salmon (Salmo salar) were not migratory: A long-standing historical debate solved through stable isotope analysis. Scientific Reports, 6: 36249. 
16. 2016 GUIRY, E., Hillier, M., Boaventura, R. et al. The transition to agriculture in Southwestern Europe: New isotopic insights from Portugal’s Atlantic coast. Antiquity 90:604-619. 
17. 2016 GUIRY, E., Szpak, P., Richards, M.P. Effects of lipid extraction and ultrafiltration on stable carbon and nitrogen isotopic compositions of fish bone collagen. Rapid Communications in Mass Spectrometry, 30: 1591-1600. 
18. 2016 GUIRY, E., Hepburn, J.C., Richards, M.P. High-resolution serial sampling for nitrogen isotope analysis of archaeological mammal teeth. Journal of Archaeological Science 69:21-28. 

Archaeology of animals 
Archaeology of agriculture 
Historical ecology
Environmental change
Isotope analyses
Environmental archaeology
Historical archaeology
Aquatic ecology
Animal behaviour
Human diet and subsistence

Select media coverage:
1. https://www.nytimes.com/2018/10/16/science/rats-cities-meat.html
2. https://www.canadiangeographic.ca/article/deforestation-19th-century-changed-chemistry-lake-ontario
3. https://gizmodo.com/human-activity-has-been-chemically-changing-the-earth-s-1826796380
4. https://theconversation.com/why-passenger-pigeons-went-extinct-a-century-ago-132736
5. https://www.thestar.com/news/gta/2016/11/08/study-sheds-light-on-extinct-lake-ontario-salmon.html
https://www.archaeology.org/news/6723-1180614-agriculture-nitrogen-cycle